Why use TDB and LMDB?

[Jeremy Allison]

On Wed, May 20, 2020 at 12:32:37PM -0700, Jeremy Allison via samba-technical wrote:
> On Wed, May 20, 2020 at 09:46:02PM +0300, hezekiah maina via samba-technical wrote:
> > Hi everyone,
> > 
> > I'm still learning Samba and one of the question I haven't figured out yet
> > is why
> > Samba uses TDB or LMDB instead of RDBMS like Postgres or MySQL?
> 
> RDBMS like Postgres or MySQL are more heavyweight than tdb and
> lmdb. i.e. we think they'll be slower. A lot slower.

Just to follow up, tdb was custom-created along with
Samba to satify *exactly* what we needed, and no more.